System running slow - EtreCheck Report

What is the date of your last backup, and by what method?

Flash Player goes end-of-life at the end of December 2020. You should have un-installed it by now.

The report says your battery is used up and needs to be replaced.

Dropbox running constantly scans your files, non-stop. if you MUST use Dropbox (which is not a Mac-Native application) you should not launch at login, but instead only launch when needed, and quit it after use.

<< Process (count) CPU (Source - Location)

Other processes 123.44 % (?) >>

when a process is using a lot of CPU, but is not specifically called out by name in the report, that is because that process is kernel_task PLUS the extensions you have glommed onto it.

These are the extensions you have added to kernel_task:

Kernel Extensions:

    /Applications/Recoverit.app

        WondershareDriver.kext (Wondershare Software Co., Ltd, 2.1.3 - SDK 10.14)

    /Applications/Turbo Boost Pro.app

        DisableTurboBoost.32bits.kext (0.0.1 - SDK 10.7)

    /Library/Extensions

        NumarkNS6Audio.kext (Ploytec GmbH, 3.2.0 - SDK 10.7)

        SixtyTwo.10.9.kext (Rane Corporation, 1.2.3f1 - SDK 10.6)

        Sl3Driver.10.9.kext (Rane Corporation, 1.3.6f1 - SDK 10.6)

        SL4.10.9.kext (Rane Corporation, 1.0.3f1 - SDK 10.6)

    /Library/StagedExtensions/Applications/Parallels Desktop.app

        prl_hypervisor.kext (Parallels International GmbH, 13.1.0 43108 - SDK 10.9)

        prl_netbridge.kext (Parallels International GmbH, 13.1.0 43108 - SDK 10.9)

        prl_usb_connect.kext (Parallels International GmbH, 13.1.0 43108 - SDK 10.9)

        prl_vnic.kext (Parallels International GmbH, 13.1.0 43108 - SDK 10.9)

    /System/Library/Extensions

        DJM-S9 USBAudio.kext (Pioneer DJ Corporation, 1.0.0 - SDK 10.7)

        SIXTY-EIGHT.10.6.kext (1.1.6f1 - SDK 10.6)

        SeratoScratchDriver.kext (2.3.0)

        APExtFramebuffer.kext (1.4 - SDK 10.8)

        DJM-900SRT USBAudio.kext (1.0.1 - SDK 10.6)

Many, many Users get by with none of these. Are you certain each and every one of these are essential?

Start by uninstalling CleanMyMac. It has been 6 days since you rebooted.